Edwaed w



(No Model.)

E. W. SERRELL, Jr.

METHOD OF AND DEVICE FOR TESTI ING THE SIZE OF SILK THREADS- No.317,223. I Patented May 5, 1885.

if. C 3

UNITED STATES,

PATENT OF ICE.

EDWARD W. snnnELL, Ja, on NEW YORK, N. Y.

METHOD OF AND DEVICE FOR TESTING THE SIZE OF SILK THREADS.

SPECIFICATION forming part of Letters Patent No. 317,223, dated May 5,1885.

Application filed June 6, 1884. (No model.) Patented in France February7, 1881,No. 141,083; in Italy February 28, 188l, No.1-2,6fi4,

and in Germany September 6, 1881, N0. 937.

To all whom it may concern.-

Be it known that I, EDWARD W. SERRELL, Jr., of the city and State of NewYork, and a citizen of the United States, now temporarily residin atChabeuil, in the Department of the Drome, in the Republic of France,have invented a Device for Testing or Measuring the Size of Threads ofSilk and Similar Elastic Filaments, of which the following is aspecification.

This device is called a serigraph, and the same has been patented in thefollowing countries: France, February 7, 1881, No. 141,083; Italy,February 28, 1881, No. 12,664; Germany, September 6, 1881, No. 18,937.

Silk filaments as drawn from the cocoon are of varying sectional areas.The sectional area is generally greatest at the outer end, anddiminishes as the filament is unwound. On this account, and because ofthe greater or less degree of skill with which the filaments arecombined in the manufacture of raw silk, this latter possesses varyingdegrees of regularity,

which it is useful to determine.

Silk possesses considerable elasticity and can be stretched from five toten per cent. in length without risk of breaking.

I have found that within the limits required by this machine there areelicited in silk when elongated resistances which are in proportion toits sectional area, and have invented a means by which this principlecan be applied to the production of mechanical movements correspondingto the changes in the size of the thread, and therefore to the testingor measuring of threads of silk or similar elastic filaments, so as toobtain an indication of all the variations in the sectional area of suchthreads.

The instrument to which this invention relates applies to the thread acertain elongation as it passes through it, and in so doing elicitsresistances of the thread, which vary with its sectional area.Thethread,while so stretched, is put into such connection with apendulous body that the pendulous body is drawn aside I from itsposition of stable equilibrium more or less, according to the varyingamounts of resistance offered by the thread. If the thread has a largesectional area or size, it will resist with corresponding force theelongation produced by the machine, and the pendulous body will be drawnaway from its position of stable equilibrium. If the thread diminishesin sectional area, it will correspondingly diminish its pull upon thependulous body,which latter will then more readily approach its positionof stable equilibrium, and variations in the size of the silk thread arethus made to cause movements of the pendulous body. A spring or similarmechanical device can be used in place of the pendulous body.

In the drawings, Figure 1 is an elevation of the apparatus, and Fig. 2is a plan of the same.

ab are two drums fixed upon the shaft 0. d is apulley or guide, aroundwhich the thread passes. This pulley is at the extremity of a rod, 2,which is supported by and moves upon the friction-wheelsee. Aspring, f,or pendulous counterweight, f, causes a variable stress upon the rod ina direction opposite to the force developed in the thread. The thread,which is supplied from any suitable bobbin or reel, is passed once orseveral times around the drum a, then around the pulley or guide d, andonce or several times around the drum b,from which it passes to anysuitable bobbin or reel, The drum b is of greater diameter than the druma,- hence the circumferential speed is greater, and the thread, as it issupplied by a and drawn along by b, is stretched by an amount determinedby the difference in circumferential speed of the two drums.

In practice I find it best to stretch a thread I of silk from one tofive per cent; hence it is subjected to a continual stretching force inpassing around the guide or pulley d, and this stretching force tends topull the guide or pulley d toward the drums to b; but the stretchingforce is resisted by the pendulous body f or spring f. If the thread asit passes becomes finer, it exerts less force upon the guide or pulleyd, and the latter moves away from the drums to b. If the thread iscoarser or stronger, it offers increased resistance to elongation, anddraws the guide or pulley (Z nearer to the drums a b. In this manner anindication is given of the varying coarseness or fineness of the threadat every point of its length by causing movements of the guide or pulleyd, and variations in the sectional area of the thread are thusindicated.A diagram can be made to record the irregularities by connecting apencil with the bar Z orpulley d, and placing a moving suriacesuch asthe cylinder tin contact with the pencil-point.

Instead of the drums of different diameters on the same shaft, drums ofthe same or different diameters on separate shafts and driven atdiflerent rates of speed may be used.

This Serigraph may be applied to any filament or thread which may besufficiently stretched to give indications of irregularities in themanner above set forth.

I claim as my invention- 1. The method herein specified of obtaining anindication or movement corresponding to the variations in the sectionalarea of athread, consisting in moving the thread along progressively,stretching the same, and sustaining a yielding device by the thread, sothat the motion of the yielding device indicates the size or strength ofthe thread or filament, sub 20 stantially as specified.

2. The combination, with two drums revolving together at differentcircumferential speeds, of a pulley or guide, and a yielding support foreach pulley or guide for operat- 25 ing on an extensible thread,substantially as specified.

Signed by me this 9th day of May, A. D. 1884.

' EDV. XV. SERRELL, JR.

\Vitnesses:

L. GROXTON, P. DURIEUX.

